US5264694A - Optical imaging system with a plurality of image planes - Google Patents
Optical imaging system with a plurality of image planes Download PDFInfo
- Publication number
- US5264694A US5264694A US07/914,828 US91482892A US5264694A US 5264694 A US5264694 A US 5264694A US 91482892 A US91482892 A US 91482892A US 5264694 A US5264694 A US 5264694A
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- US
- United States
- Prior art keywords
- surface sensors
- image planes
- another
- image
- imaging system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 238000012634 optical imaging Methods 0.000 title claims abstract description 6
- 230000003287 optical effect Effects 0.000 claims abstract description 14
- 230000005693 optoelectronics Effects 0.000 claims abstract description 6
- 238000003384 imaging method Methods 0.000 claims description 6
- 239000011159 matrix material Substances 0.000 abstract description 5
- 238000011156 evaluation Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000000295 complement effect Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C11/00—Photogrammetry or videogrammetry, e.g. stereogrammetry; Photographic surveying
- G01C11/02—Picture taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
- H04N23/10—Cameras or camera modules comprising electronic image sensors; Control thereof for generating image signals from different wavelengths
- H04N23/13—Cameras or camera modules comprising electronic image sensors; Control thereof for generating image signals from different wavelengths with multiple sensors
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
- H04N25/40—Extracting pixel data from image sensors by controlling scanning circuits, e.g. by modifying the number of pixels sampled or to be sampled
- H04N25/41—Extracting pixel data from a plurality of image sensors simultaneously picking up an image, e.g. for increasing the field of view by combining the outputs of a plurality of sensors
Definitions
- the invention is directed to an optical imaging system having a plurality of separate image planes in which, in each instance, there is a plurality of rectangular or square surface sensors which are arranged at a distance from one another and in turn comprise a number of optoelectronic sensor elements arranged in rows and columns, and having optical means which are adjusted or adjustable in such a way that they image the same object portion on every image plane.
- Such an imaging system is known from DE-A1 34 28 325 which describes an imaging system which is also usable for photogrammetric purposes and in which four optically parallel beam paths can be represented by means of four individual lenses.
- the four individual lenses are adjusted in such a way that the same object section is imaged in the four resulting image planes.
- four square surface sensors are arranged at distances relative to one another which are smaller than their own width. These surface sensors can be CCD sensor blocks formed in the manner of a matrix from optoelectronic sensor elements.
- the quadruplicate groups of these surface sensors are offset relative to one another from one image plane to the other in such a way that the imaged object section is covered without gaps by the totality of surface sensors when the four image planes are optically superimposed.
- the cost in apparatus incurred by the use of four lenses is thus relatively high in this known imaging system.
- due to the relatively small distances between the surface sensors there is considerable overlapping in certain boundary or edge areas of the surface sensors so that image points situated in these areas are detected two or even three times in all by sensor elements of different image planes.
- the invention therefore has the object of providing an optical imaging system of the type indicated in the beginning which makes do with an apparatus-related cost which is reduced as far as possible and is as efficient as possible with respect to image evaluation.
- This object is met according to the invention by the following characteristic features: there are only three separate image planes; surface sensors of identical width are arranged at a distance from one another in adjacent parallel rows in every image plane; the distances between the surface sensors within one row are greater than their width and are, at the same time, given by the sum of the widths of one of the surface sensors located in each of the two other image planes; the surface sensors in two immediately adjacent rows are offset relative to one another by more than their own width; the grids of surface sensors formed in this way are offset relative to one another from one image plane to the other in such a way that the imaged object section is detected without gaps by the totality of surface sensors when the image planes are optically superimposed.
- the imaging system of the invention makes do with only three separate image planes.
- the respective optical means can be formed by three separate lenses or by less than three lenses and, additionally, by semipermeable mirrors or prisms.
- the lenses, and also the mirrors, if used, must be adjusted in such a way that the same object section is imaged in every image plane.
- the surface sensors arranged in parallel rows in the individual image planes are at distances from one another within the rows which are greater than their respective widths.
- the surface sensors arranged in two immediately adjacent rows are offset relative to one another by more than their own width and thus do not contact one another and are arranged "on gaps" so to speak. This takes into account the fact that the surface sensors, which comprise e.g.
- the statements made here respecting width and distances of the surface sensors refer to their optically sensitive surfaces containing sensor elements. Due to the mutual offsetting of the surface sensors in immediately adjacent rows, a grid of surface sensors arranged at regular intervals occurs in every image plane. The distances between the surface sensors within a row, apart from the fact that they are to be greater than their own width, are dimensioned in such a way that they correspond exactly to the sum of the widths of one of the surface sensors situated in each of the remaining two image planes.
- the grids of surface sensors produced in this way are offset relative to one another in the three image planes in such a way that the entire image surface is covered by surface sensors without gaps or overlapping when optically superimposed.
- the contents of the image are accordingly detected in their entirety with the lowest possible expenditure on sensor elements.
- the surface sensors in all three image planes have the same width. In this case, it is advisable that the surface sensors located in two immediately adjacent rows be offset relative to one another by 1.5 times their width. However, it is not absolutely necessary that all surface sensors have the same width; rather, surface sensors of different widths can be used from one image plane to the other.
- FIG. 1 shows an optical imaging system according to the invention in the form of a digital camera with a lens and two semipermeable mirrors;
- FIGS. 2a to 2c show an arrangement of surface sensors of the same width in three separate image planes
- FIG. 2d shows the optical superposition of the grids of surface sensors according to FIGS. 2a to 2c;
- FIG. 3 shows the optical superposition of three grids of surface sensors of different widths.
- a conventional aerial camera for example, has a picture ratio or image format of approximately 23 ⁇ 23 cm 2 with a resolution of e.g. 100 line pairs/mm, depending on the film which is used.
- a digital camera having the same resolution would then have to use e.g. a CCD surface sensor with 23,000 ⁇ 23,000 sensor elements arranged in a matrix. Such surface sensors are not available for the foreseeable future.
- a digital camera 1 according to FIG. 1 can be carried e.g. by aircraft or satellites for taking pictures of the surface of the overflown terrain. Of course, it can also be used for other recording purposes. It comprises a lens 2 and two semipermeable mirrors 3 and 4 arranged one after the other in the path of the beam. These mirrors 3 and 4 are advisably inclined at an angle of 45° relative to the optical axis 5.
- the semipermeable mirror 3 can be constructed e.g. in such a way that it lets through two thirds of the incident intensity and reflects one third, guiding it to the image plane E A associated with it.
- the second semipermeable mirror 4 can then advisably be constructed in such a way that it lets through one half of the incident intensity and reflects the other half.
- Two additional separate image planes E B and E C are associated with this second semipermeable mirror 4.
- the three image planes are covered by grid-like arrangements of surface sensors approximately corresponding to FIGS. 2a to 2c. These grids are offset relative to one another from one image plane to the other in such a way that the object section OA being imaged, e.g. a rectangular or square section of a planar terrain surface, is detected by the surface sensors of the three image planes without gaps as a whole, as will be made clear in the following.
- FIGS. 2a to 2c A possibility for the arrangement of surface sensors in three separate image planes which is preferred for its simplicity is indicated in FIGS. 2a to 2c.
- surface sensors A of identical width d A are arranged at equal distances ⁇ A in a first image plane E A in immediately adjacent, parallel rows R 1 to R 6 .
- the distances ⁇ A of the surface sensors A equal twice their width d A .
- the surface sensors A are offset relative to one another in two directly adjacent rows, e.g. R 1 and R 2 , by exactly 1.5 times their width d A . Accordingly they are arranged "on gaps" and their corners have a sufficient distance from one another so that there is also no mutual interference of the optically insensitive edges of the individual surface sensors A which enclose the shown surfaces and are not shown in the
- this surface sensor in turn also comprises optoelectronic sensor elements S, e.g. of the CCD type, which are arranged in the manner of a matrix, i.e. in lines and gaps.
- FIGS. 2b and 2c there are also surface sensors b and c in an edge region of the image planes E B and E C shown in the drawing. These surface sensors b and c serve only to complement the entire usable image surface to form a complete rectangle when the three image planes are optically superimposed according to FIG. 2d.
- FIG. 2d shows the optical superposition of the three image planes E A to E C shown in FIGS. 2a to 2c.
- the three grids of surface sensors A, B, C merge with one another without gaps or overlapping in such a way that the image of the object section OA is divided without gaps into image elements which are alternately associated with surface sensors A, B, C and b and c of the three different separate image planes.
- To achieve such a covering without gaps it is necessary to provide for a correspondingly exact positioning of the surface sensors in the individual image planes at the inner walls of the camera 1 and for an exact adjustment of the semipermeable mirrors.
- FIG. 3 illustrates an example showing that the surface sensors to be arranged in the three separate image planes need not have the same width.
- the optical superposition of three image planes is shown.
- Surface sensors D are arranged in the first of these image planes
- surface sensors E and e are arranged in the second image plane
- surface sensors F and f are arranged in the third image plane, specifically according to the distribution given in FIG. 3.
- the surface sensors D, E and F have the same widths and also meet the rest of the requirements to be realized in the invention with respect to the widths and distances.
- the invention provides the possibility of taking digital, large surface area pictures with high resolution at a cost in optoelectronic sensor elements and optical auxiliary means which is reduced to the greatest possible extent.
- the sensor elements are preferably CCD sensors which can be read out in a conventional manner.
- optical superposition primarily refers to the purely fictitious, i.e. imaginary, superposition of the three image planes, wherein the deflection of the beam paths by the semipermeable mirrors 3 and 4 can be negated conceptually and the image planes E A and E B accordingly "fall" on the image plane E C , together with the grids of surface sensors A, B and C associated with them.
- the total image is first assembled from the image point information of the surface sensors associated with the three separate image planes by electronic means in the course of the digital image evaluation.
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- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Transforming Light Signals Into Electric Signals (AREA)
Abstract
Description
Claims (3)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE4123791A DE4123791C2 (en) | 1991-07-18 | 1991-07-18 | Digital area camera with multiple optics |
DE4123791 | 1991-07-18 |
Publications (1)
Publication Number | Publication Date |
---|---|
US5264694A true US5264694A (en) | 1993-11-23 |
Family
ID=6436437
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US07/914,828 Expired - Fee Related US5264694A (en) | 1991-07-18 | 1992-07-15 | Optical imaging system with a plurality of image planes |
Country Status (5)
Country | Link |
---|---|
US (1) | US5264694A (en) |
EP (1) | EP0529200B1 (en) |
JP (1) | JPH05336423A (en) |
CA (1) | CA2074127C (en) |
DE (2) | DE4123791C2 (en) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5694165A (en) * | 1993-10-22 | 1997-12-02 | Canon Kabushiki Kaisha | High definition image taking apparatus having plural image sensors |
WO1999031870A2 (en) * | 1997-12-15 | 1999-06-24 | Analog Devices, Inc. | Spatially offset, row interpolated image sensor |
US6456339B1 (en) | 1998-07-31 | 2002-09-24 | Massachusetts Institute Of Technology | Super-resolution display |
US6473119B1 (en) * | 1997-04-08 | 2002-10-29 | Carl-Zeiss-Stiftung | Photogrammetic camera |
US20020163582A1 (en) * | 2001-05-04 | 2002-11-07 | Gruber Michael A. | Self-calibrating, digital, large format camera with single or mulitiple detector arrays and single or multiple optical systems |
US6523956B2 (en) | 2000-05-09 | 2003-02-25 | Jon Oshima | Multiplexed motion picture camera |
GB2418512A (en) * | 2001-10-26 | 2006-03-29 | Symbol Technologies Inc | Pixel array for an imaging system |
US20060087712A1 (en) * | 2004-10-21 | 2006-04-27 | Harper Steven L | Light modulator |
DE102005005211A1 (en) * | 2005-02-03 | 2006-08-10 | Inpho Gmbh | Optical surface sensor geometrical adjustment device, has three charged coupled device-surface sensors on three focal planes, and beam splitter in path of rays between lens and surface sensors and splitting ray on focal planes |
US20080055600A1 (en) * | 2006-08-25 | 2008-03-06 | Hiroshi Kawaguchi | Defect inspection apparatus |
US20090268983A1 (en) * | 2005-07-25 | 2009-10-29 | The Regents Of The University Of California | Digital imaging system and method using multiple digital image sensors to produce large high-resolution gapless mosaic images |
CN104166225A (en) * | 2014-08-18 | 2014-11-26 | 西北工业大学 | Imaging device with multiple imaging planes and imaging method |
WO2015158812A1 (en) * | 2014-04-16 | 2015-10-22 | Spheronvr Ag | Camera arrangement |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4309959A1 (en) * | 1993-03-26 | 1994-09-29 | Christofori Klaus Dr | Method and device for local filtering of objects of any structure |
DE4422366C1 (en) * | 1994-06-27 | 1996-01-04 | Siemens Ag | X=ray diagnostic appts. with detector elements arranged in matrix |
US5856888A (en) * | 1996-05-13 | 1999-01-05 | Ait Corporation | Split beam optical character reader |
DE19816561C1 (en) * | 1998-04-15 | 1999-11-11 | Wolf D Teuchert | Camera for taking aerial photos |
EP1312892A1 (en) * | 2001-11-20 | 2003-05-21 | Wolf D. Dr. Teuchert | Detector arrangement for capturing an image strip |
DE10339439A1 (en) * | 2003-08-25 | 2005-03-24 | Michael Olders | Digital camera for taking pictures or a timed sequence of pictures has a system of mirrors, light-sensitive sensors and a data-processing unit |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4634882A (en) * | 1985-02-19 | 1987-01-06 | Karmar Research Partnership | Optical device for displaying a large two dimensional image |
US5130814A (en) * | 1988-12-23 | 1992-07-14 | Gecmarconi Limited | Video recording and reproducing apparatus including dual offset ccd image arrays |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2652586B2 (en) * | 1975-04-29 | 1981-05-27 | Elektro-Optik GmbH & Co KG, 2392 Glücksburg | Process for generating and displaying thermographic images |
GB1564733A (en) * | 1975-10-30 | 1980-04-10 | Xerox Corp | Arrangement for extending photosensor array resolution |
US4204230A (en) * | 1978-10-25 | 1980-05-20 | Xerox Corporation | High resolution input scanner using a two dimensional detector array |
US4591901A (en) * | 1984-03-30 | 1986-05-27 | Rca Corporation | Television camera with solid-state imagers mounted to a prism |
JPS60247369A (en) * | 1984-05-23 | 1985-12-07 | Dainippon Screen Mfg Co Ltd | Method and device for improving resolution of array sensor |
DE3428325C2 (en) * | 1984-08-01 | 1992-01-02 | Wilfried Prof. Dr.-Ing. 3013 Barsinghausen Wester-Ebbinghaus | Arrangement of opto-electrical solid-state sensor surfaces in the photogrammetric imaging system |
DE3616400A1 (en) * | 1985-05-23 | 1986-11-27 | Steinheil-Lear Siegler AG, 8045 Ismaning | Optoelectronic image converter |
-
1991
- 1991-07-18 DE DE4123791A patent/DE4123791C2/en not_active Expired - Fee Related
-
1992
- 1992-04-29 EP EP92107252A patent/EP0529200B1/en not_active Expired - Lifetime
- 1992-04-29 DE DE59207416T patent/DE59207416D1/en not_active Expired - Fee Related
- 1992-07-15 US US07/914,828 patent/US5264694A/en not_active Expired - Fee Related
- 1992-07-16 JP JP4189596A patent/JPH05336423A/en active Pending
- 1992-07-17 CA CA002074127A patent/CA2074127C/en not_active Expired - Fee Related
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4634882A (en) * | 1985-02-19 | 1987-01-06 | Karmar Research Partnership | Optical device for displaying a large two dimensional image |
US5130814A (en) * | 1988-12-23 | 1992-07-14 | Gecmarconi Limited | Video recording and reproducing apparatus including dual offset ccd image arrays |
Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5694165A (en) * | 1993-10-22 | 1997-12-02 | Canon Kabushiki Kaisha | High definition image taking apparatus having plural image sensors |
US6473119B1 (en) * | 1997-04-08 | 2002-10-29 | Carl-Zeiss-Stiftung | Photogrammetic camera |
WO1999031870A2 (en) * | 1997-12-15 | 1999-06-24 | Analog Devices, Inc. | Spatially offset, row interpolated image sensor |
WO1999031870A3 (en) * | 1997-12-15 | 1999-09-10 | Analog Devices Inc | Spatially offset, row interpolated image sensor |
US6166831A (en) * | 1997-12-15 | 2000-12-26 | Analog Devices, Inc. | Spatially offset, row interpolated image sensor |
US6456339B1 (en) | 1998-07-31 | 2002-09-24 | Massachusetts Institute Of Technology | Super-resolution display |
US6523956B2 (en) | 2000-05-09 | 2003-02-25 | Jon Oshima | Multiplexed motion picture camera |
US7009638B2 (en) | 2001-05-04 | 2006-03-07 | Vexcel Imaging Gmbh | Self-calibrating, digital, large format camera with single or multiple detector arrays and single or multiple optical systems |
US20020163582A1 (en) * | 2001-05-04 | 2002-11-07 | Gruber Michael A. | Self-calibrating, digital, large format camera with single or mulitiple detector arrays and single or multiple optical systems |
GB2418512A (en) * | 2001-10-26 | 2006-03-29 | Symbol Technologies Inc | Pixel array for an imaging system |
GB2418512B (en) * | 2001-10-26 | 2006-07-05 | Symbol Technologies Inc | Semiconductor device adapted for imaging bar code symbols |
US20060087712A1 (en) * | 2004-10-21 | 2006-04-27 | Harper Steven L | Light modulator |
US7136210B2 (en) | 2004-10-21 | 2006-11-14 | Hewlett-Packard Development Company, L.P. | Light modulator |
DE102005005211A1 (en) * | 2005-02-03 | 2006-08-10 | Inpho Gmbh | Optical surface sensor geometrical adjustment device, has three charged coupled device-surface sensors on three focal planes, and beam splitter in path of rays between lens and surface sensors and splitting ray on focal planes |
US20090268983A1 (en) * | 2005-07-25 | 2009-10-29 | The Regents Of The University Of California | Digital imaging system and method using multiple digital image sensors to produce large high-resolution gapless mosaic images |
US20080055600A1 (en) * | 2006-08-25 | 2008-03-06 | Hiroshi Kawaguchi | Defect inspection apparatus |
US8077306B2 (en) * | 2006-08-25 | 2011-12-13 | Hitachi High-Technologies Corporation | Defect inspection apparatus |
WO2015158812A1 (en) * | 2014-04-16 | 2015-10-22 | Spheronvr Ag | Camera arrangement |
CN104166225A (en) * | 2014-08-18 | 2014-11-26 | 西北工业大学 | Imaging device with multiple imaging planes and imaging method |
Also Published As
Publication number | Publication date |
---|---|
DE4123791C2 (en) | 1995-10-26 |
CA2074127A1 (en) | 1993-01-19 |
CA2074127C (en) | 1998-01-06 |
EP0529200A1 (en) | 1993-03-03 |
JPH05336423A (en) | 1993-12-17 |
EP0529200B1 (en) | 1996-10-23 |
DE4123791A1 (en) | 1993-01-21 |
DE59207416D1 (en) | 1996-11-28 |
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